x1,y1,x2,y2=map(float,input().split())
print('{0:.6f}'.format(((x1-x2)**2 + (y1-y2)**2 )**(.5))) x1,y1,x2,y2=map(float,input().split()) x1 map(float,input().split()) map float input().split() ().split () input split y1 x2 y2 print('{0:.6f}'.format(((x1-x2)**2 + (y1-y2)**2 )**(.5))) print '{0:.6f}'.format(((x1-x2)**2 + (y1-y2)**2 )**(.5)) '{0:.6f}'.format '{0:.6f}' format ((x1-x2)**2 + (y1-y2)**2 )**(.5) (x1-x2)**2 + (y1-y2)**2 (x1-x2)**2 x1-x2 x1 x2 2 (y1-y2)**2 y1-y2 y1 y2 2 .5 x1,y1,x2,y2=map(float,input().split()) map(float,input().split()) x1 x2,y2=map(float,input().split()) map(float,input().split()) x2 y1,x2,y2=map(float,input().split()) map(float,input().split()) y1 y2=map(float,input().split()) map(float,input().split()) y2
x1,y1,x2,y2=map(float,input().split())
print('{0:.6f}'.format(((x1-x2)**2 + (y1-y2)**2 )**(.5)))